/*
 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.nulldev.util.graphics.renderIt.ginterfaces.marlin.impl.pisces.stats;

/**
 * Generic histogram based on long statistics
 */
public final class Histogram extends StatLong {

	static final int BUCKET = 2;
	static final int MAX = 20;
	static final int LAST = MAX - 1;
	static final int[] STEPS = new int[MAX];

	static {
		STEPS[0] = 0;
		STEPS[1] = 1;

		for (int i = 2; i < MAX; i++) {
			STEPS[i] = STEPS[i - 1] * BUCKET;
		}
	}

	static int bucket(int val) {
		for (int i = 1; i < MAX; i++) {
			if (val < STEPS[i]) {
				return i - 1;
			}
		}
		return LAST;
	}

	private final StatLong[] stats = new StatLong[MAX];

	public Histogram(final String name) {
		super(name);
		for (int i = 0; i < MAX; i++) {
			stats[i] = new StatLong(String.format("%5s .. %5s", STEPS[i], ((i + 1 < MAX) ? STEPS[i + 1] : "~")));
		}
	}

	@Override
	public void reset() {
		super.reset();
		for (int i = 0; i < MAX; i++) {
			stats[i].reset();
		}
	}

	@Override
	public void add(int val) {
		super.add(val);
		stats[bucket(val)].add(val);
	}

	@Override
	public void add(long val) {
		add((int) val);
	}

	@Override
	public String toString() {
		final StringBuilder sb = new StringBuilder(2048);
		super.toString(sb).append(" { ");

		for (int i = 0; i < MAX; i++) {
			if (stats[i].count != 0l) {
				sb.append("\n        ").append(stats[i].toString());
			}
		}

		return sb.append(" }").toString();
	}
}
